Ciphering machine



Aug. 11, 1936. E. BRAUER I CIPHERING MACHINE Filed May 2. 1930 4 Sheets-Sheet l 2 16 a J a o 30 OESA ABCDEFGH KLMNOPQR Aug. 11, 1936.

' BRAUER CIPHERING- MACHINE 4 Sheets-Sheet 2 mr llllmg F iled May 2. 1950 Elma/whom Aug. 11, 1936. E BRAUER 2,050,919

CIPHERING MACHINE Filed May 2. 1950 4 Sheets-Sheet s Eexvs 75/921: 05/? Aug. 11, 1936. E. BRAUER CIPHERING MACHINE Filed May 2. 1930 4 Sheets-Sheet 4 Ill swam boa Patented Aug. 11, 1936 UNITED STATES PATENT OFFICE Application May 2, 1930, Serial No. 449,326

7 In Germany May 2, 1929 3 Claims.

In many ciphering machines there are elements, which will cause certain exchanges of the signs of the plain text. These elements are styled the basic cipher key. These elements present in the arrangement are used in changing sequence. 'By period the number of successive symbols is to be understood, according to which the basic key is again operated in the same succession, or a certain word is rendered by the same ciphers. The technical problem is to render said period as large as possible. According to the invention n'rieans are provided to utilize the basic cipher key provided in the machine as perfectly as possible. This is effected in that the elements, which in the basic key correspond with the exchanging alphabet, are used in succession in a sequence, which will closely correspond. to the mathematical possibility of their permutations, so that in case n such elements are arranged, the period will approximately be n.(n--1)., (n-2) 3, 2, '1

Several forms of construction of an arrangement according to the invention are illustrated by way of example in the drawings.

Figure 1 shows a construction of the apparatus of this kind partly in longitudinal section, partly in view.

Figures 2 and 20; show two alphabet cylinders with a partof a corresponding ciphering and deciphering alphabet and thejacket surrounding each cylinder, pa'rtly broken away. I

Figure 3 shows the alphabet cylinder arrangement with the gear of Figure 1 partly in longitudinal section, partly in view.

Figure 4 represents the same device partly in vertical cross section, partly in view.

Figure 5 shows another modification in which the selection of the switching steps is effected automatically, represented partly in view "and partly in lohgitudinalsection.

, Figure 6 shows the same arrangement in vertical cross section and partly in view.

Figure '7 shows the same arrangement partly in horizontal section and partly in plan.

Figure 8 shows a detail of Fig. 7 in a perspective view and on an enlarged scale.

Figure 9 shows the same arrangement in section on line IXIX of Figure 5.

Figure 10 shows a detail of Fig. 9 in a perspective view and on an enlarged scale.

In the modification according to Figures 1 and 4, 'I represents a shaft rotatably jou rnalled in the apparatus, 3 is a cylindrical tube "connected with the saidshaft, 2 is a cylinder carrying on its peripheral surface several, for instance 23, exchanging alphabets arranged in an axial direction.

The cylinder 2 is slipped over the inner cylinder and carried along by the latter when 5 rotating, by means of a ball rest I55. 4 represents a mantle 'or jacket secured to the body of the apparatus. 220 is a footed support attached thereto. 5 is an opening in the said jacket 4, through which the number of the alphabet 10 marked the cylinder 2 becomes visible. 6 is an opening through which becomes visible the appurtenant alphabet of the cylinder 2. I5 is a ratchet-wheel secured to the shaft I and preventing by means of the pawl I6 a retrograde motion of the machine.

The ratchet wheel I4 is likewise secured to the shaft I and is engaged by the catch I3, which is connected with the gear-wheel 25 (Figs. 3 and 4). The catch I3 is rotatably disposed on a pin secured in the wheel 25. The gear-wheel is loosely mounted on the shaft 1.

The gear 25 is actuated by way of the gear wheel I5I through the rack 24, which is actuated by the key iI connected with said rack. The 25 rack 24 is provided with a stop 9 (Figs. 1 and 4)., whose motion on the one hand is limited by the bottom portion 1 of the machine and on the other hand by the displaceable slide '8 adapted to be clamped resiliently in notches I20. 223. is an extension of the slide 8 against the bottom of which abuts the stop 9. 224 is a pin on slide 8 adapted to be actuated by finger pressure, the end 221 of which engages in the notches I20.

On the shaft I there is furthermore arranged the ratchet-wheel I 51 keyed to shaft I, which is engaged by a pawl I5? which is actuated by the stop 9 of the rack 24 shortly prior to its reaching the lowest position (Figure 4), so that the portion of the machine able to be turned and consisting of the parts I, 2, 3, I5, I59, I51, I55 is locked and prevented from being moved owing to its inertia beyond the desired position. Pawl I58 is provided with a tooth-shaped end 225 which engages in the locking teeth of ratchet wheel I51 when the rack 24 strikes against the other end 226 of pawl I58. The spring IBI (Fig.

1) serves for raising again the key bar 24. A member 22] is attached to the lower end of spring I6I which member slides in a slotted tube 222 and which extends sufiiciently far from the tube 222 that it is taken along by the stop 9 which is fixed upon the key bar 24. The machine is operated in the following manner: By turning the cylinder 2 by means of the part I59 55 the desired initial alphabet iscaused to become about a definite arc is effected and a new alphabet is rendered visible in the opening 6, in which the next letter is selected in the same manner.

After the selection of one or a pluralityof let.

ters theposition of the slide 8 is changed. The. magnitude of the step is registered each time by the user of the machinein the cipher text which is for instance noted on paper in order to allow subsequent deciphering. This note indicates to.

the person deciphering which magnitude of steps he must adjust.

erably one less than the number of alphabets on the cylinder 2 (for instance 22). The change of the magnitude of the step in general is efiected after a few letters, 'for instance five,fso that whole words characteristic of the text, are not ciphered. by the same length of step. I change of step represents extra work. On the other hand the ciphering will become the more reliable the more often a change of step is carried out: Although each change ofsteprenders the 'ciphering more involved, on the otherhand,

the ciphering becomes more. reliable the, more often a change of step is executed.

The driving mechanism consisting of a rack 24 and a gear wheel MI is capable of imparting to the alphabet drum at each step, rotary motions which extend up to a'complete revolution q al to 360. In this 'way, full utilization of the cipher alphabet is insured, since, at each step, any one of them may follow anyoth'er.

In the previously described apparatus, accord-r ing to Figs. 1 and 4, it was necessary to actuate the lever 8 and adjust'it differently for each change of the magnitude of the step. Furthermore, the:

key H had to be depressed for each letter. To combine both operations and to so arrange it that the change in the magnitude of the step is effected also by the motion required per'se for each letter, a mechanism is provided in Figs. 3

to 6a, which shows a modified form of construc tion for the variable step changing and contains further improvements of the invention and which after a few strokes will change the engaging position of the stop 9. of the rack ill (Figs. 7 and 8). 10 is a crown gear drive 'ad vanced one'tooth' at each stroke. The crown gear drive rotates about pin' 28B which 'is provided with a hub 28!. This motion to the ex: tent of one tooth is due to the fact that the edge 7 H of the rack 84 (Figs. 6 and 10) catches 'betweentwo teethof the crown gear'drive I0, so that the edge H in engaging with an inclined. tooth of the crown drive 'Hl'rotates this crown drive a distance equal to the Width of one tooth.

The rack 24 with its teeth 599 is in engagementwith the gear wheel 8?. 72 represents .aiball which is forwardly spring-pressed (Figs. 9 and 10) engaging the teeth 73 and fixing the position of the crown drive. stance after five strokes of the rack 84 or alternatively after 5, 3, 2. 5, 3, 2 strokes will advance the gear wheel by one tooth. The 5 The number. of the notches in which the slide 8 is clamped is pref- Each 54 are pins, which for ingear I50 is secured with a gear wheel 15 (Figs. 6 and 7) of' similar design to the same shaft. The pins 14, with the aid of the wheel I50 and of the wheel '15 (Fig. 9), which, for instance, is

provided with twelve teeth, turn the drum Tl ample thirteen teeth 2I9, or in any case, a number of teeth which is different from and cannot be divided into equal fractions like the number of teeth of the wheel 16. The wheel 19 transmits its movement to the disk 254 by means of a spring 8! The spring 81 is a short spiral spring, one end of which is fixed to the wheel 19 and the other end to the disk 254. On the disk'25 deepenings 255 are arranged, in which a suitable spring 21! engages (Figs. 6 and 8), which in turnis'fixed on the ring 25! of the drum 80. Both drums wand 11 are adapted to be adjusted'by hand. The drum 80 is adjustable by means of knurled ring 25!, and the drum il by 256., Both drums 8H and T! are loosely mounted upon shaft 256. They carry the stops I63, which correspond to the stops formed in Figs. 1 and 4 by'the slide '8 and by the bottom portion l, and

form the'limitingstops of they stop 9 of the rack 91 in Figs. -6 and 7, which correspond to the slide 8. For instance, they are providedwith thirteen and twelverows, respectively, namely, as many rows as the wheels 19 and 16 have teeth. Each row has, for' example, seven screw-threaded holes so that one of the drums has 12 times 7 or 84' screw-threaded holes 303 and the other one, 13 times 7 or 91. holes, into which is screwed, in each row, a steel pin I63. The stop 9 can move up and down each time between a pin 163 of the drum T! and a pin I63 of the drum 89. This stop 9 is in the shape of a capital letter H (Fig: 8). It therefore forms afork which embraces a pin I63 of the drum Bland prevents it and consequently the drum 80 from continuing to rotate. Owing to the resilient connection 8i, the parts 10, 14,150, 16, TI, 15 and I9 can also move when a pin I63 of the drum 80 is arrested-by the stop 9..The operator will besignalled the position of the pins M at a certain situation by the actuation of a signal, for instance by a bell 82 (Fig. 9), being struck by a lever 25'! moved by a pin 74 on wheel 10 when said pin engages said lever. The lever 25? is provided with an abutment 2l3, which is struck by the pins M upon the crown gear drive 10 at the rotation of the latter. 500 is a spring stop which yieldingly holds the wheel 16 in position. 56! arethe guides for the rack 99. The wheel 19 is provided with a hub 202. 'The shaft 256 is enlarged at 204, upon which the striking pin 285 is fixed, which serves to hold the spring 8!. 206 is the hub of the disc 254 which has a recess 20? which operates in the manner that upon the rotation of shaft 256, the parts 254 and 80 may remain behind slightly, in the event that the stop 9 evenly embraces the pin I63 so that a 203 indithe outfit against damage incase of violent'depressions of the key lever85. The key lever is provided with a finger key 2I4 and is rotatably mounted upon a pin 2H5 fixed upon the arm 2I'I attached to the housing. Upon the lever 85 is provided a connecting pin 2I2 for the lower end of spring, 86 while the upper end of the spring 88 is suspended from a pin 2 fixedly attached to the rack 84. The rack 84 engages the gear wheel 81, which is connected to the spring 83. The gear wheel 81 is connected with one end of the spring 99 whose other end is connected with the spring casing 88' firmly united with the gear wheel 89. The spring 99 will admit of the gear wheel 81 continuing to move, even if the wheel 89 is prevented from further motion, when the engaging rack 9| touches, by means of the stop 9, a pin arranged on the drums TI and 89. The gear wheel 81 keeps on turning to allow the rack 84 to continue on its way to the lowermost point and to move the crown gear drive 19. A spring 92 serves for returning the gear wheel 89. The spring 92 hugs a grooved roll MI and tends to turn it back and thus the wheel 99. The wheels 81, 89 meshing, respectively, with the racks 84 and 9|, are cog Wheels, one-half of either one being shown in Fig. 6 (see also Figs. 5 and 7). In order to avoid imperfect strokes owing to negligence which are possible in the form of construction shown in Figures 1 and 4, a lock is provided on the rack 84 consisting of two racks, having oppositely arranged teeth 93 and 94, a double pawl 95, a snapping compression spring 96, which will force said pawl either to the right or to the left side, the stop 91 and the counter-stops 98 and 99, which will reverse the pawl in the highest and lowest position. Then only a complete downward or upward motion is possible each time. 2I8 is a lever arm which is fixedly attached to the double pawl and against which presses the spring 96. 2I5 is a locking tooth rigidly attached to the double pawl 295 which engages in the rack 94. In lieu of the safety device I51, I58 shown in Figures 1 and 4 against the swinging beyond a certain point, a positive clutch coupling I99 is arranged, which can be reversed by means of the fork I9I arranged on the lever I92 and the stops I93 and I94, mounted on the rack 84. The clutch I99 comprises two rims having rectangular teeth, one rim being firmly connected with the gear wheel 89 and the other one slidingly connected, in known manner, with the alphabet cylinder 6 so as to cooperate in the rotation thereof, though it can be displaced by the fork I9! to such an extent that it can alternately engage or not engage the other rim. The resilient catch I22 causes the notched wheel I2I having as many notches as there are ciphering alphabets as well as the alphabet part 5 always to be held in proper position. The clutch I99 is always in engagement during the downward movement and always disengaged during the upward movement of the rack 84. I2I is a notched wheel ensuring the accurate adjustment of the portion able to be turned by means of the resilient catch I22.

I65 represents a ratchet-wheel, which is firmly connected with the notched wheel I2I and the alphabet part 6 and will prevent a retrograde motion of the rotary portion by means of the pawl I66.

The operation of the device is as follows: Through a few strokes the crown drive is brought into a first position, which is found out by the ringing of the bell. The position of the drums I1 and 89 can be marked by means of letters in each row of pin holes. By means of the knurled rings 259 and 253 the two drums canbe brought into any desired position. The initial position of the two drums is noted in the ciphered text for enabling the deciphering. During each stroke the turning ofthe parts I2! and I65 with which the alphabet cylinder is connected in the same manner as 2 in Figure l with the shaft I, corresponds to the travel of the stop 9 between a pin I63 of the drum I1 and a pin I63 of the drum 89. tioned the toothed wheel 16 has twelve and the toothed wheel I9 thirteen teeth, the travel of the stop 9 alters in such a manner that it again assumes the same values successively after l2 13=156 changes. Ifonly one drum were present having for example thirteen rows of holes, the travel of the stop 9 would again change in the same manner after every thirteen changes. The drums I7 and 89 are brought into a position indicated, which can be ascertained by means of letters at each row of pin holes. The further operation consists in that, after each letter the key lever 85 is depressed once. The difference of the magnitude of the step for the drum rotation is automatically adjusted by the limiting of the travel of 9 between the pins I63. The notched wheel I2I and the ratchet wheel I65 are in Figures 5 to 9 keyed on a shaft which corresponds to the shaft I in Figures 1 and 4. Of the other corresponding parts in Fig. 1, namely I, 2, 3, 4, 5, 6, I55, I59 and I69 only the parts 4, 5 and 6 are indicated in Fig. '7.

With both constructions deciphering is effected by the introduction of another cylinder, (which does not differ externally from the cylinder 2), carrying alphabets which in the sense explained below correspond to those on the first cylinder. The two cylinders corresponding to the cylinder 2 in Figs. 1 and 4 are designated 2a and 2b in Figs. 2 and 2a, the cylinder 2a serving for ciphering and the other cylinder 2b for deciphering. The first letters of the code alphabet on the cylinder 2a, which is just being used for ciphering, are B F G A C E D. On the deciphering cylinder 2b are found the letters D A E G F B C. In the code alphabet, the letter A is replaced by B and, correspondingly, in the deciphering alphabet the letter B by A. In the code alphabet, the letter B is replaced by F and, correspondingly, in the deciphering alphabet the letter F by B, and so forth. For example, if the word FACE is ciphered with the ciphering alphabet assumed in Fig. 2, the symbol EBGC will be produced by the designation of the cylinder 2a. In order to decipher EBGC, the cylinder 21) must be exchanged for the cylinder 2a where EBGC corresponds again to FACE. 299 is one of the code alphabets upon the cylinder 2a corresponding to the code alphabet upon the cylinder 2 in Fig. 3. 2H! is one of the deciphering alphabets upon the cylinder 2b. I69 is the plain alphabet upon the jacket or mantle 4. 298 is an enlargement with a knurled hand grip I59a. upon the inner cylinder 2a.

In order to be able to easily change the basic key, it is preferably pasted upon the cylinders 2 in the form of series of alphabets printed on paper.

In addition it is of much importance, that the portions able to .be turned possess as small an inertia as possible, in order to reduce the impacts of the stop 9 against the pins I63 occurring As in the examples men-' during the operation and which, extend to. the limit of the solidity of the material. For that reason the rotating parts, according to'the invention are made of .light metal for example aluminium as far as permissible, in particular the cylinders" 2 and the attaching body 3.

I claim: r

1. A' ciphering machine having a. number of code alphabets, in which the sequence of letters Within each code alphabet remains the same 7 during ciphering and deciphering operations,

said code alphabets being arranged in rows on the surface of a cylinder, a plain alphabetconnected with a stationary part of the machine and a device for rotating said cylinder, said de-,

vice comprising a gear wheel, a gear having a plurality of, teeth adapted to mesh with said wheel, and means for moving said gear to various extents such that the said gear wheel and the cylinder connected therewith are rotated through some of the various angles up to nearly 360.

2. A ciphering machine having a number of code alphabets, in which the sequence of letters Within" each code alphabet remains the same during ciphering and deciphering operations, said code alphabets being arranged in rows on the surface or a cylinder, a plain alphabet connected with a stationary part of the machine, a,

device 'for rotating said cylinder, said device comprising a gear .wheel, a gear having a plurality of teeth-.adaptedto mesh with said Wheel, means for movingsaid gear to various extents such'that the said gear wheel and the cylinder connected therewith are rotated. through some of. the various angles up to nearlyv360, and an adjustable stop for limiting the: magnitude of the motion of the said gear. i

rality of teeth adapted to mesh with said wheel,

means for moving said gear torvarious extents such that the said gear wheel and the cylinder connected therewith arerotated through some of the various angles up to nearly 360, and an adjustable stop for-limiting the magnitude of the motion of the said gear, said. stop being automatically adjusted after a, predetermined number of motions of the said gear.

ERNST BRAUER. 

